P.S. Couple of things, flour or matzo mail is a personal preference, I like the flour, because back in Ukraine matzo was a prize posation and was only available during Pesah, maybe a few month after and nobody would waist it on latkes. After all thare are better things that could be made with that. Also oil, I hate the smell of fried canola oil, it smells like fish oil, if you are a child of the 60-s then you know what I'm talikng about, brrrrrrr. Corn oil, or sunflour oil is my choice.

My Hungarian grandma use to take leftover mashed potatoes add a couple egg yolks, beat the whites separately, fold them in, season (if needed) and fry but we never called those potato pancakes latkes. Latkes were always made with raw potatoes/